Serious Adverse Events Significantly Reduce Patient-Reported Outcomes at 2-Year Follow-up: Nonoperative, Multicenter, Prospective NIH Study of 105 Patients.

STUDY DESIGN: This is an analysis of a prospective 2-year study on nonoperative patients enrolled in the Adult Symptomatic Lumbar Scoliosis (ASLS) National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) trial.

OBJECTIVE: The purpose was to evaluate the impact of serious adverse events (SAEs) on patient-reported outcomes (PROs) in nonoperative management of ASLS as measured by Scoliosis Research Society-22 (SRS-22), Oswestry Disability Index (ODI), and Short Form-12 (SF-12) at 2-year follow-up.

SUMMARY OF BACKGROUND DATA: Little is known about PROs in the nonoperative management of ASLS or the prevalence and impact of SAEs on PROs.

METHODS: The ASLS trial dataset was analyzed to identify adult lumbar scoliosis patients electively choosing or randomly assigned to nonoperative treatment with minimum 2-year follow-up. Patient data were collected prospectively from 2010 to 2015 as part of NIAMS R01-AR055176-01A2 "A Multi-Centered Prospective Study of Quality of Life in Adult Scoliosis." SAEs were defined as life-threatening medical events, new significant or permanent disability, new or prolonged hospitalization, or death.

RESULTS: One hundred five nonoperative patients were studied to 2-year follow-up. Twenty-seven patients (25.7%) had 42 SAEs; 15 (14.3%) had a SAE during the first year. The SAE group had higher body mass index (29.4 vs. 25.2; P = 0.008) and reported worse SRS-22 Function scores than the non-SAE group at baseline (3.3 vs. 3.6; P = 0.024). At 2-year follow-up, SAE patients experienced less improvement (change) in SRS-22 Self-Image (-0.07 vs. 0.26; P = 0.018) and Mental Health domains (-0.19 vs. 0.25; P = 0.002) than non-SAE patients and had lower SRS-22 Function, Self-Image, Subscore, and SF-12 Mental and Physical component scores (MCS/PCS). Fewer SAE patients reached minimal clinically important difference (MCID) threshold in SRS-22 Mental Health (14.8% vs. 43.6%; P = 0.01).

CONCLUSION: A high percentage (25.7%) of ASLS patients managed nonoperatively experienced SAEs. Those patients who sustained a SAE had less improvement in reported outcomes.

LEVEL OF EVIDENCE: 2.